This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Studies have linked cigarette smoking and tobacco use to carcinogenesis in multiple organs of the human body and premature skin aging. We are currently investigating mechanisms of how cigarette smoke alters fibroblast and keratinocyte behavior. OBJECTIVE: In order to provide a better understanding of the physiological and morphological changes in the human skin due to tobacco smoke exposure, we examined the relationship between fibroblast activity and cigarette smoke condensate (CSC) using organotypic tissue-engineered skin models (RAFTs). MATERIALS AND METHODS: RAFTs constructed using adult and neonatal cell lines were exposed to 0, 10, 25, and 50 [unreadable]g/mL of CSC for 14 days. RAFT dimensions were measured to calculate contraction over time. Multi-photon microscopy was also performed to image collagen structure. On an adult cell line, cell viability and apoptosis were studied using fluorescence dye systems and confocal microscopy. RESULTS: This study identified a dose-dependent relationship between contraction and CSC concentration. Fiber structure changed after CSC exposure as well. Exposure to CSC resulted in apoptosis and cell death. CONCLUSION: These findings suggest that CSC has a cytotoxic effect on RAFTs and thus fibroblast activity, which may be linked to the physiological and morphological changes that are observed in human skin exposed to second-hand cigarette smoke.